Reconstitution de la végétation et du paléoclimat à partir de charbons de bois prélevés sur les sites du Paléolithique dans la région de Jungwon en Corée

Hundreds samples of the charcoals and waterlogged woods excavated from three late Paleolithic sites (Suyanggae, Gunang-gul and Sorori) in the Jungwon Region in Korea were analyzed to reconstruct the vegetation and paleoclimate in the region. Analyzed charcoal samples from the Suyanggae site show that the climate was cold in the lower part and it became more warm and dry in the upper part. From the Gunang-gul site, only Picea spp. was identified, indicating cool climates. From the Sorori site, two species were found; Alnus spp. (95%) and Ulmus spp. (5%). No conifers were discovered. The species composition indicates that the climate condition of central Korean peninsula around 8,800 BP was little cooler and wetter condition.     

Phylogeny of <Emphasis Type="Italic">Gunnera</Emphasis>

 The phylogeny of the genus Gunnera is investigated for the first time. Twelve species representing the six currently recognised subgenera are analysed. Two chloroplast DNA regions, the rbcL gene and the rps16 intron, together provide 46 informative characters out of 2335. A combined analysis of both genes gives four most parsimonious trees, firmly establishing the east South American G. herteri as sister group to the rest of the genus. The African G. perpensa is sister group to two well-supported clades, one including the South American subgenera Misandra and Panke, the other the Australian/New Zealand/Malayan species of subgenera Milligania and Pseudogunnera. Thus, South America is a composite area for Gunnera, showing up at two different levels in the cladogram. Our analysis supports a close biogeographic relationship between Australia and New Zealand. The evolution of some morphological characters is discussed. Lastly, the unusual structure of some of the rbcL sequences is reported. Received July 6, 2000 Accepted October 24, 2000     

Dynamic data replacement and adaptive scheduling policies in spark

Improper data replacement and inappropriate selection of job scheduling policy are important reasons for the degradation of Spark system operation speed, which directly causes the performance degradation of Spark parallel computing. In this paper, we analyze the existing caching mechanism of Spark and find that there is still more room for optimization of the existing caching policy. For the task structure analysis, the key information of Spark tasks is taken out to obtain the data and memory usage during the task runtime, and based on this, an RDD weight calculation method is proposed, which integrates various factors affecting the RDD usage and establishes an RDD weight model. Based on this model, a minimum weight replacement algorithm based on RDD structure analyzing is proposed. The algorithm ensure that the relatively more valuable data in the data replacement process can be cached into memory. In addition, the default job scheduling algorithm of the Spark framework considers a single factor, which cannot form effective scheduling for jobs and causes a waste of cluster resources. In this paper, an adaptive job scheduling policy based on job classification is proposed to solve the above problem. The policy can classify job types and schedule resources more effectively for different types of jobs. The experimental results show that the proposed dynamic data replacement algorithm effectively improves Spark's memory utilization. The proposed job classification-based adaptive job scheduling algorithm effectively improves the system resource utilization and shortens the job completion time.

     

L'hominidé du Pléistocène supérieur en Corée

Since the middle of 1970s, one rock-shelter, six caves and one open archaeological site have yielded several hominid fossils. Among them, fossils from Yonggok, Mandal, Sangsi and Hungsu cave sites are useful to reconstruct the general shape of the Upper Pleistocene Hominids in Korea. The main study of this paper is to focus on the reconstruction of the general shape of the upper Pleistocene hominids, and to examine the cause of cranial changes from the late upper Paleolithic to Mesolithic period in Korea. Biomechanical principles are also applied to reconstruct the social activity of the upper Paleolithic man in Korea. In addition, it is assumed that main proponent of Paleolithic cultures in Korea might be Homo sapiens rather than any other species. Based on the anatomical characteristics of skull, the axillary border of the scapular and the midshaft of the femur, general appearance of Homo sapiens during the Pleistocene in Korea could be reconstructed.     

« Flûte » et pointes de la Grosse Badlhöhle, Autriche

The Grosse Badlhöhle (Austria, Steiermark) is the origin of one of the most perfect bone points of the early Aurignacian and one of the best perforated femurs of the same period, which can be regarded as musical instruments. Two other fragments of points raise intriguing questions on the first Homo sapiens sapiens which cannot be solved today but will contribute to future research. A review on the debate of Palaeolithic flutes will follow with experimental proofs of boring artificial holes with high quality pictures on the blow-hole and the lack of gnawing traces on the opposite face. The musical possibility of an instrument with only one hole is discussed with ethnographic analogies. Hafting, optimal conditions of strength and possible use of arrows will close the discussion on the Badlhöhle bone artefacts.     

Le groupe des « bisons adossés » de Lascaux. Étude de la technique de l'artiste par analyse des pigments

The painting matter of the “back to back bison's panel” of Lascaux was examined and analysed by electron microscopy in order to understand the know-how of Magdalenian artists. The observation of several samples coming from specific areas of the two bisons give an access to the nature of the used pigments, to the preparation mode used to obtain various colours and also to the application mode. Thanks to this physicochemical approach, we can make hypotheses about the mind and the gestures of the artists.     

Variability of esterase patterns in adult flies of the <Emphasis Type="Italic">saltans</Emphasis> species group of <Emphasis Type="Italic">Drosophila</Emphasis> (subgenus <Emphasis Type="Italic">Sophophora</Emphasis>)

Esterases are known for their involvement in several physiological processes and high degree of polymorphism, in many organisms. Such polymorphism has been used to characterize species and species groups and to study genetic changes occurred in their evolutionary history. In the present study, the esterase patterns of 19 strains from 10 species representative of the five subgroups of the saltans species group were analyzed using polyacrylamide gel electrophoresis and α- and β- naphthyl acetates as substrates. Fifty-one esterase bands were detected and classified as 31 α-esterases, 18 β-esterases and two α/β-esterases. On the basis of the inhibition patterns using Malathion and eserine sulfate, 34 bands were classified as carboxylesterases, 14 as acethylesterases and three as cholinesterases. Ten gene loci were tentatively established on the basis of data on band position in the gel, substrate preference and inhibition pattern. Twenty bands were species-specific, the remaining being shared by species from the same or different subgroups. Bands detected exclusively in males and bands with a different frequency or degree of expression between sexes were also detected. In the gels prepared for analysis of gene expression in the body parts (head, thorax and abdomen), the degree of expression of the β-esterases was higher in the thorax, while the α-esterases were expressed predominantly in the abdomen and thorax. A global view of the data available at present on the esterases of the species from the saltans group and their degree of polymorphism are presented, as well as the possibility of using some β-esterases, because of their characteristics in the gels, as markers for species identification.     

Peculiarities of Ca<Superscript>2+</Superscript>-regulation of functional activity of myocardium of frog <Emphasis Type="Italic">Rana temporaria</Emphasis>

To elucidate role of intra- and extracellular Ca²⁺ in regulation of rhythm and strength of frog heart contractions, there were studied ECC and isometric contraction of myocardium preparations in response to verapamil, adrenaline, and blockers of α- and β-adrenoreceptors. It has been shown that after an intramuscular injection of verapamil (6 mg/kg), bradycardia develops, the heart rate (HR) decreasing by 50–70%. Further, the cardiac arrest occurred; however, administration to the animals of adrenaline (100 mg/kg) restored the cardiac rhythm for a short while. After an intramuscular injection of adrenaline at doses of 0.1–10 mg/kg, no essential changes were observed in the potential action amplitude and HR; an increase of the administered adrenalin concentration to 100 mg/kg was not accompanied by the cardiac rhythm stimulation, as this takes place in homoiothermal animals and human; on the contrary, an essential HR deceleration was revealed. Phentolamine (5 mg/kg) gradually decelerated HR rhythm by 32–45%. The potential amplitude changed insignificantly. A subsequent intracardiac injection of adrenaline (100 mg/kg) on the background of block of α-adrenoreceptors produced acceleration of the rhythm (by 15–21%) and fall of the electrogram amplitude. These results can indicate that in the frog heart phentolamine interacts predominantly with α 1-adrenoreceptors. An intracardial administration of propranolol (1 mg/kg) to frogs promoted inhibition of β-adrenergic receptors and produced a gradual cardiac rhythm deceleration. In experiments on assessment of verapamil effect on the character of contractions this preparation at a concentration of 150 μM was established to produce a significant dose-dependent decrease of the contraction strength. A rise of verapamil concentration in the sample to 200 μM led to a decrease of the amplitude, on average, by 68–70% and in individual preparations—by 80–85%; however, administration into the sample of adrenaline (10 μM) restored the cardiac contraction strength. Adrenaline (1 nM–100 μM) increased markedly the contraction amplitude. Phentolamine (10 μM) did not inhibit transmission of contractile signal to cardiomyocytes; this was manifested in that the contraction amplitude after addition of adrenaline (10 μM) into the sample was approximately the same as in the sample containing no phentolamine. Propranolol (10 μM) eliminated the stimulatory action of adrenaline (10 μM). The results of these experiments indicate that in the frog ventricular cardiomyocytes the main adrenaline acceptors are β-adrenoreceptors.     

Isolation of <Emphasis Type="Italic">madA</Emphasis> homologs in <Emphasis Type="Italic">Pilobolus crystallinus</Emphasis>

Pilobolus crystallinus shows unique photoresponses at various growing stages. cDNAs for putative photoreceptors were cloned from this fungus. Three genes named pcmada1, pcmada2, and pcmada3 were identified from the PCR fragments, and amplified with degenerated primers for the LOV domain, which is conserved in many blue-light receptors. Deduced amino acid sequences for PCMADA1, PCMADA2, and PCMADA3 had one light-oxygen-voltage (LOV)-sensing and two PER-ARNT-SIM (PAS) domains. A zinc finger DNA-binding motif was conserved in the C-terminals of PCMADA1 and PCMADA3. However, PCMADA2 lacked the zinc finger motif. Expression of pcmada1 was suppressed by blue light whereas that of pcmada3 was promoted by blue-light irradiation.     

La stratigraphie du Pléistocène supérieur et le Paléolithique en Corée

In Korea, Quaternary deposits are characterized by marine and fluvial terrace deposits, commonly found in the coastal areas and at the sides of river valleys. The major terraces are classified into 5 different levels, i.e., alluvial plain (3-5 m asl), lower terrace (10-25 m asl), middle terrace (33-50 m asl), high terrace (55-85 m asl), and highest terrace (90-160 m asl). They were formed by the repetition of sedimentation and erosion due to sea level fluctuation and uplifting along the coastal areas during Quaternary period. The formation age of the lower marine terraces at the level of 10-20 m is interpreted to be the last interglacial (75-125 Ka, MIS = 5a-5e). The middle coastal terrace gravels distributed at the level of about 33-45 m above mean sea level and are to be formed before the last interglacial. Above coastal terrace deposits, slope deposits and paleosol layers are overlain and freezing and thawing crackings were developed in them. Major prehistory archaeological sites in the coastal areas are found in the slope deposits formed during last glaciations. The upper parts of the slope deposits are typified by paleosol layers with typical frost cracks (soil wedges) and frangipanes. As geochronological bases for subdividing Paleolithic cultures, two typical paleosol layers are useful because they are mostly found and imprinted with several horizons of frost cracks or soil wedges. The uppermost crack structures were formed under the boreal-periglacial climatic regime during the last glacial period of extremely cold-dry climate in Korea. The upper pedogenetic sediments containing frost cracks or soil wedges were formed between 24 and 17 Ka in many Paleolithic profiles. The lowermost paleosol layer with frost cracks (soil wedge), strongly attacked into hillslope sediments or last interglacial saprolite layers on the weathered basement rocks, were detected at least as old as 59-74,000 Ka. Lastly upper Paleolithic cultural layers were found in the young fluvial deposits, which had been formed since the Last Glacial Maximum (LGM). Some of them were particularly continued as late as the Pleistocene-Holocene Transition Period.     

Proteolysis of <Emphasis Type="Italic">α</Emphasis>-amylase from <Emphasis Type="Italic">Saccharomycopsis fibuligera</Emphasis>: characterization of digestion products

α-Amylase from Saccharomycopsis fibuligera R-64 was successfully purified by butyl Toyopearl hydrophobic interaction chromatography, followed by Sephadex G-25 size exclusion and DEAE Toyopearl anion exchange chromatography. The enzyme has a molecular mass of 54 kDa, as judged by SDS PAGE analysis. Upon tryptic digestion, two major fragments with relative molecular masses of 39 kDa and 10 kDa, which resemble the A/B and C-terminal domains in the homologous Taka-amylase, were obtained and were successfully separated with the Sephadex G-50 size exclusion column. The 39-kDa fragment demonstrated a similar amylolytic activity to that of the undigested enzyme. However, it was found that the K _m value of the 39-kDa fragment was about two-times higher than that of the undigested enzyme. Moreover, thermostability studies showed a lower half-life time for the 39-kDa fragment. These findings suggest that the 39-kDa fragment is the catalytic domain, while the 10-kDa fragment is the C-terminal one, which plays a role in thermostability and starch binding. Although the undigested enzyme is able to act on raw starches at room temperature, with maize starches as the best substrate, neither the undigested enzyme nor the fragments adsorb the tested raw starches. These results propose Saccharomycopsis fibuligera α-amylase as a raw starch-digesting but not adsorbing amylase, with a similar domain organization to that of Taka-amylase A.     

Calculations of the C<Subscript>2</Subscript> fragmentation energies of higher fullerenes C<Subscript>80</Subscript> and C<Subscript>82</Subscript>

The C₂ fragmentation energies of the most stable isolated-pentagon-rule (IPR) isomers of the C₈₀ and C₈₂ fullerenes were evaluated with second-order Møller-Plesset (MP2) theory, density-functional theory (DFT) and the semiempirical self-consistent charge density-functional tight-binding (SCC-DFTB) method. Zero-point energy, ionization energy and empirical C₂ corrections were included in the calculation of fragmentation energies for comparison with experimental C₂ fragmentation energies of the fullerene cations. In the case of the most probable Stone-Wales pathway of C₂ fragmentation of C₈₀, the calculated \(D_{0} {\left( {{\text{C}}_{{{\text{80}}}} ^{ + } } \right)}\) agree well with experimental data, whereas in the case of C₈₂ fragmentation, the calculated \(D_{0} {\left( {{\text{C}}_{{{\text{82}}}} ^{ + } } \right)}\) exceed by up to 1.2 eV the experimental ones, which suggests that other IPR isomers may be present in sufficient amounts in experimental samples. Computer-intensive MP2 calculations and DFT calculations with larger basis sets do not yield much improved C₂ fragmentation energies, compared to those reported earlier with B3LYP/3-21G. On the other hand, semiempirical approaches such as SCC-DFTB, which are orders of magnitude less intensive, yield satisfactory fragmentation energies for higher fullerenes and may become a method of choice for routine calculations of fullerenes and carbon nanotubes.

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Figure C₂ fragmentation energies of C₈₀ and C₈₂ fullerenes have been calculated with B3LYP/6-31G* model chemistry, with semiempirical self-consistent-charge density-functional tight-binding (SCC-DFTB) method and with the more rigorous MP2 method. The influence of basis set extension and level of theory on the resulting fragmentation energies is discussed

     

Genetics of the cell cycle: Adaptive modification of the <Emphasis Type="Italic">CycB</Emphasis><Superscript><Emphasis Type="Italic">2g</Emphasis></Superscript> mutation expression in dividing cells of <Emphasis Type="Italic">Drosophila melanogaster</Emphasis>

The effect of mutation CycB ^2g on mitosis in neural ganglia and imaginal disks was studied in third-instar larvae of Drosophila melanogaster. Chromosome condensation and segregation were shown to be impaired in dividing cells of mutant larvae. During the three-year period of maintenance of the mutation in heterozygote, frequencies of some defects decreased via cellular adaptive modification.Translated from Genetika, Vol. 41, No. 3, 2005, pp. 312–319.Original Russian Text Copyright © 2005 by Lebedeva, Trunova, Omelyanchuk.     

Typification of <Emphasis Type="Italic">Metrosideros regelii</Emphasis> (<Emphasis Type="Italic">Myrtaceae</Emphasis>) and consideration of its generic position

Summary  The type specimen of Metrosideros regelii is discussed. It contains a mixture of two species, representing different genera, and a lectotype is chosen. The generic position of the species is considered in the light of morphology and recent molecular evidence and the new combination, Mearnsia regelii, made.     

Effects of sugars and growth regulators on <Emphasis Type="Italic">in vitro</Emphasis> growth of <Emphasis Type="Italic">Dactylorhiza</Emphasis> species

The influence of sugars and growth regulators on shoot and root growth of Dactylorhiza species was studied under in vitro conditions. The seedling development was stimulated with the application of glucose and sucrose at concentration of 10 g dm⁻³ each. The improvement of shoot growth rate and shoot length was enhanced by cytokinins N ⁶-(2-isopentenyl)adenine or N ⁶-benzyladenine and their combination with auxin indolebutyric acid (IBA). The root growth rate and root length of seedlings increased in the presence of IBA and α-naphthaleneacetic acid. Individual Dactylorhiza species showed statistically significant differences in shoot and root development depending on sugar and growth regulator combinations.     

<Emphasis Type="Italic">In vitro</Emphasis> propagation of ten threatened species of <Emphasis Type="Italic">Mammillaria</Emphasis> (Cactaceae)

Mammillaria species are the most numerous within Cactaceae family, and some of them are threatened with extinction as a result of human activities. In this work, results of in vitro propagation are presented for ten Mammillaria species, testing 20 combinations of indole-3-acetic acid (IAA) and kinetin. Best results on shoot formation were obtained using kinetin at two levels: 27.9 and 46.5 μM. All IAA levels tested were able to induce de novo shoot formation in M. bocasana, M. densispina, M. hahniana, M. hutchisoniana, M. orcutii, M. pectinifera, M. perbella, M. picta, M. rhodantha, and M. zephyranthoides. Depending on the IAA level tested, four responding groups were observed concerning their highest shoot-formation number. For all species, the highest average of shoot formation was achieved with 5.7:46.5 or 11.4:46.5 μM IAA/kinetin, yielding 4.8 and 4.7 shoots per explant, respectively, in 60 d. Rooting of regenerated shoots was achieved by leaving the explants in their shoot-induction medium or transferring them to half-strength MS medium. Hardening of regenerated plants was successfully achieved by planting them in peat moss substrate after a desiccation treatment at room temperature for 3 d.     

Resolution-optimized NMR measurement of <Superscript>1</Superscript>D<Subscript>CH</Subscript>, <Superscript>1</Superscript>D<Subscript>CC</Subscript> and <Superscript>2</Superscript>D<Subscript>CH</Subscript> residual dipolar couplings in nucleic acid bases

New methods are described for accurate measurement of multiple residual dipolar couplings in nucleic acid bases. The methods use TROSY-type pulse sequences for optimizing resolution and sensitivity, and rely on the E.COSY principle to measure the relatively small two-bond ²D_CH couplings at high precision. Measurements are demonstrated for a 24-nt stem-loop RNA sequence, uniformly enriched in ¹³C, and aligned in Pf1. The recently described pseudo-3D method is used to provide homonuclear ¹H-¹H decoupling, which minimizes cross-correlation effects and optimizes resolution. Up to seven ¹H-¹³C and ¹³C-¹³C couplings are measured for pyrimidines (U and C), including ¹D_C5H5, ¹D_C6H6, ²D_C5H6, ²D_C6H5, ¹D_C5C4, ¹D_C5C6, and ²D_C4H5. For adenine, four base couplings (¹D_C2H2, ¹D_C8H8, ¹D_C4C5, and ¹D_C5C6) are readily measured whereas for guanine only three couplings are accessible at high relative accuracy (¹D_C8H8, ¹D_C4C5, and ¹D_C5C6). Only three dipolar couplings are linearly independent in planar structures such as nucleic acid bases, permitting cross validation of the data and evaluation of their accuracies. For the vast majority of dipolar couplings, the error is found to be less than ±3% of their possible range, indicating that the measurement accuracy is not limiting when using these couplings as restraints in structure calculations. Reported isotropic values of the one- and two-bond J couplings cluster very tightly for each type of nucleotide.     

Characterization and functional analysis of hsp21.8b: An orthologous small heat shock protein gene in Tribolium castaneum

Small heat shock proteins (sHSPs) act as molecular chaperones and are widely distributed in all kinds of organisms. Comparative analysis revealed that an orthologous shsp was present during insect evolution. Here, hsp21.8b, one insect orthologous shsp, had been identified in Tribolium castaneum. Quantitative real‐time PCR illustrated that Tchsp21.8b was expressed in all developmental stages, along with the lowest expression at early embryonic stage and relative high expression at other stages especially in late eggs and late pupae. In the adult period, Tchsp21.8b exhibited the highest expression level in central nervous system and followed in elytron, epidermis, ovary and fat body. Moreover, it was upregulated 3.39‐fold in response to enhanced heat stress (45°C) for 4 hr but not to cold stress (4°C) and was upregulated by 1.73‐ to 1.94‐fold under ultraviolet (UV) exposure during 4–6 hr. It was also downregulated by 20.8%–41.8% under starvation in 3 days and had a “down‐up‐down” trend under the pathogen stresses. Larval RNA interference of Tchsp21.8b caused 40.6% insects mortality and reduced the oviposition amount by 66.0% and only 21.0% of the ds‐Tchsp21.8b eggs could hatch into larvae. These results suggested that as an orthologous shsp, Tchsp21.8b not only plays important roles in the growth, development and fecundity of T. castaneum but with the competence to resist the environment stresses, although the response is relatively weak compared to other hsps. Results from this study also uncovered the functions of the orthologous shsp in the development and anti‐stresses ability of T. castanuem. It provided more scientific evidence for revealing the physiological mechanisms of shsps of the insects and enhanced the capabilities to control different pests.